Page 231 - DCAP407_DATA_STRUCTURE

Data Structure

void preorder(struct node *r) //Define preorder function
{
/*Checks if r is not equal to NULL*/
if(r!=NULL)

{
printf("\t %d",r->data); //Prints the data of the node
/ *Recursively call preorder passing the address of the left sub-tree*/
preorder(r->left);
/ *Recursively call preorder passing the address of the right sub-tree*/
preorder(r->right);
}
}

void postorder(struct node *r) //Define postorder function
{
if(r!=NULL) //Checks if r is not equal to NULL
{
/ *Recursively call postorder passing the address of the left sub-tree*/
postorder(r->left);

/ *Recursively call postorder passing the address of the left sub-tree*/
postorder(r->right);
printf("\t %d",r->data); //Prints the data of the node
}
}
void main()
{

int no; //Declare variable no
int choice; //Declare variable choice
clrscr();
printf("\n Enter the root:");
scanf("%d",& no); //Reads the number entered
root=make(no); //Initialize the number to root

p=root; // Value of root is then assigned to variable p
while(1) //Checks the conditions provided in while loop
{
/*Prints the statement “Enter another number*/
printf("\n Enter another number:"); scanf("%d", &no);
//Reads the number entered
/*Conditional statement, check if no is equal to -1*/

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